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A dwelling unit that is modest in size, typically consisting of a few rooms.
El apartamento pequeño tiene una cocina compacta.
The small apartment has a compact kitchen.
Often used to describe modest living spaces.
In Spanish, 'pequeño' can refer to both physical size and modestness, so context matters.
From Spanish 'apartamento' (from French 'appartement') and adjective 'pequeño' (from Latin 'parvus').
Common in everyday speech; not a technical term.